Rewrite git/gerrit/gerrit-int urls to googlesource

BUG=chromium:281665,chromium:290413

TEST=None

Change-Id: Ie3167f5f7196f9f3be7f2bf46da69cf4e35512ec
diff --git a/common.mk b/common.mk
index 058e906..7939883 100644
--- a/common.mk
+++ b/common.mk
@@ -7,7 +7,7 @@
 #
 # NOTE NOTE NOTE
 #  The authoritative common.mk is located in:
-#    http://git.chromium.org/gitweb/?p=chromiumos/platform/common-mk.git
+#    https://chromium.googlesource.com/chromiumos/platform/common-mk.git
 #  Please make all changes there, then copy into place in other repos.
 # NOTE NOTE NOTE
 #